A Nationwide survey of safety protocols and chemosensory assessments by Japanese clinicians pre- and post-COVID-19 pandemic

OBJECTIVE

There has been an increase of attention and awareness of smell and taste loss due to the impact of COVID-19. However, little is known about the influence of COVID-19 on the number of psychophysical tests performed, the timing of these tests, or the protection protocols employed to protect against virus transmission. This study aimed to explore the changes in examination approaches, types of tests employed, and safety measures adopted by clinicians before and after the COVID-19 pandemic.

METHODS

A survey was distributed to 404 institutes of the Oto-Rhino Laryngological Society of Japan, consisting of otolaryngologists working in university hospitals, general hospitals, and private clinics. The anonymous online survey contained questions related to safety measures and chemosensory assessments performed before and after the COVID-19 pandemic. Specifically, participants were queried on the number and types of examinations conducted, the type of examiners who performed them, the timing of tests in suspected and non-suspected COVID-19 cases, modifications made due to the pandemic, and the protective measures adopted during chemosensory examinations.

RESULTS

Of the 201 respondents, representing a 50 % response rate, 49 % were from general hospitals, 48 % from university hospitals, and 3 % from private clinics. The study found a slight decrease in the overall number of chemosensory tests conducted post-COVID-19. In terms of who performed the test, there were no differences pre- and post- COVID-19. Most examinations (52-68 %) for suspected COVID-19 cases were performed 1-2 months after the onset of symptoms. Modifications in testing rooms and personal protective equipment (PPE) were reported by the majority of institutions post-pandemic. While different examination rooms or PPE were not commonly used based on a patient's previous COVID-19 diagnosis, changes were observed in testing practices. Most examinations were conducted in rooms with windows or fans, and PPE usage was high; surgical masks, eye visors or face shields, and disposable gloves being commonly used. Virus transmission from patient to examiner was reported in only one case during T&T olfactometer examination.

CONCLUSION

We investigated the impact of the COVID-19 pandemic on the number of olfactory and gustatory tests performed, the type of examiner, the examination room, and the use of PPE and found no significant difference before and after the COVID-19 pandemic on these factors. Adherence to a protection protocol involving the proper use of PPE in controlled environments enabled the continuation of olfactory and gustatory tests during the pandemic.

Evaluation of odor recognition threshold measurement methods in T&T olfactometry: A survey study

OBJECTIVE

The odor recognition thresholds in T&T olfactometry are measured by either the examiner's judgment of the patients' odor expression for each standard odor or by the patient's choice of the correct response from an olfactory term table. This study aimed to clarify the correct odor expressions and use of the olfactory term table.

METHODS

A questionnaire was administered to otolaryngologists or medical staff in charge of testing at facilities where T&T olfactometry is performed. The questionnaire consisted of the facility's background, environment and procedures of T&T olfactometry, choice of the correct answer with five different standard odors, and use of the olfactory term table. For the choices, the expressions used were those considered correct at Nippon Medical School Tama Nagayama Hospital and the Kyoto Nose and Allergy Clinic.

RESULTS

A total of 81 valid responses were obtained. Most respondents belonged to medical and educational institutions (59.3%, 48/81). The laboratories in the respondents' institutions were completely ventilated using various methods. Clinical laboratory technicians inspected 51.7% (45/81) of the facilities. The order of standard odors in the odor recognition threshold test differs depending on the facility. When the examiner was unsure about the answer given by the patient in the odor recognition threshold test, 16.1% (9/56) of the respondents chose "present the olfactory term table," 33.9% (19/56) chose "increase the concentration," and 37.5% (21/56) chose "present the olfactory term table" or "increase the concentration," depending on the situation. A total of 96.4% (54/56) of the facilities treated odor expressions other than those in the olfactory term table as correct, and the odor expressions that were considered correct differed from facility to facility. Of the respondents, 80.2% (65/81) answered "I know the olfactory term table," and the mean value of satisfaction with the current olfactory term table was 4.4 ± 3.0. Of the respondents, 81.5% (53/65) answered that "the timing of presenting the olfactory term table should be standardized in all facilities."

CONCLUSION

In the odor recognition threshold test by T&T olfactometry, this study revealed that the odor expressions considered as correct answers for the standard odors and the use of the olfactory term table differed among facilities.

AQUACEL® Ag Advantage reduces the stress of postoperative packing removal after endoscopic sinus surgery

OBJECTIVE

After Endoscopic Sinus Surgery (ESS), packing plays an important role in wound healing and hemostasis. However, the effect of the packing removal procedure on physician stress has not been evaluated. The purpose of this study was to evaluate physician stress during packing removal for patients treated with AQUACEL® Ag Advantage versus KALTOSTAT®.

METHODS

This retrospective study included 15 patients who underwent packing with ESS for chronic rhinosinusitis performed at two centers; 9 were treated with AQUACEL® Ag Advantage and 6 were treated with KALTOSTAT®. Physician stress during packing removal was evaluated with the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). The time required to remove the packing and the number of instruments used in the procedure were recorded. Postoperative bleeding (Boezaart bleeding score) and wound healing were graded. Patient symptoms on the day after surgery and pain during packing removal were assessed using a visual analog scale.

RESULTS

Computed tomography scores, asthma complications, and blood eosinophil counts were significantly higher in the AQUACEL® Ag Advantage group. Patient symptoms on the day after surgery were not significantly different between the two groups. Physician stress during the task of packing removal was significantly lower in the AQUACEL® Ag Advantage group than in the KALTOSTAT® group (35.5 vs. 81.0, p=0.016) according to the NASA-TLX scores. The number of instruments used in the procedure was significantly lower in the AQUACEL® Ag Advantage group than in the KALTOSTAT® group (3.0 vs. 6.0, p=0.015). There were no significant differences in procedure time for packing removal, postoperative bleeding, wound healing, or patient pain at the time of packing removal between the groups.

CONCLUSION

Physicians feel stressed about packing removal. In addition, AQUACEL® Ag Advantage is useful for packing after ESS, requiring fewer instruments for the procedure than KALTOSTAT® and reducing physician stress about the procedure.

LEVEL OF EVIDENCE

Level 3.

Impact of infectious disease pandemics on individual lifetime consumption: An endogenous time preference approach

This paper considers the impact of the coronavirus disease 2019 (COVID-19) pandemic on long-term individual lifetime consumption profiles. The framework for the analysis is a model that extends Strulik (2021) to include the government sector, where time preference is determined by individual health damage (deficit) distinct from normal aging. Thus, the health damage caused by COVID-19 changes the rate of time preference and consequently affects the Euler equation for consumption. Our theoretical contribution is the consistent incorporation of public health investment into the existing model to understand the effect of government measures against a pandemic. Numerical analysis based on this model is used to estimate changes in health status over time, trends in the rate of time preference, and individual lifetime consumption profiles, taking into account differences in age at the time of the pandemic and the nature of the government responses. Because the long-term negative economic impact would be enormous, we should avoid advocating for "living with COVID-19" without due consideration. The reopening of the economy must be accompanied by a commitment to the containment and elimination of infections with future novel coronaviruses.

Barrier Factors of Adherence to Dupilumab Self-Injection for Severe Allergic Disease: A Non-Interventional Open-Label Study

PURPOSE

The status of dupilumab self-injection at home is not well understood. We therefore aimed to identify the barriers to adherence to dupilumab self-injection.

PATIENTS AND METHODS

This non-interventional open-label study was conducted between March 2021 and July 2021. Patients with atopic dermatitis, bronchial asthma, and chronic rhinosinusitis with nasal polyps receiving dupilumab, from 15 sites, were requested to complete a self-administered questionnaire regarding the frequency and effectiveness of dosing as well as their use and satisfaction with dupilumab. Barriers to adherence were assessed using the Adherence Starts with Knowledge-12.

RESULTS

We included 331 patients who used dupilumab for atopic dermatitis (n = 164), chronic rhinosinusitis with nasal polyps (n = 102), and bronchial asthma (n = 65). The median efficacy of dupilumab scored 9.3 on the visual analog scale. Overall, 85.5% of the patients self-injected dupilumab, and 70.7% perfectly complied with the established injection dates. The pre-filled pen was significantly superior to the conventional syringe in terms of usability, operability, ease of pushing the plunger, and patient satisfaction. However, the pre-filled pen caused more pain during self-injection than did the syringe. Multivariate logistic regression analysis showed that adherence decreased with longer dupilumab treatment duration (p = 0.017) and was not associated with age, sex, underlying disease, or device type. There was a difference in responses related to "inconvenience/forgetfulness" between the good and poor adherence groups.

CONCLUSION

The pre-filled dupilumab pen was superior to the syringe in terms of usability, operability, ease of pushing the plunger, and satisfaction. Repetitive instructions are recommended for preventing poor adherence to dupilumab self-injection.

Convergent movement of COVID-19 outbreak in Japan based on SIR model

The infection dynamics of COVID-19 show frequent phases in which the infection spreads rapidly, resembling explosive infection. However, despite the repeated increases and decreases, there is a process of convergence even within a relatively short period of time. While it is obvious that the growth rate of the cumulative number of infected people slows down as it increases, considering the infectious disease process, we also observe a slowdown in the growth rate of the net number of infected people. Moreover, there exists a special type of convergence whereby areas with initially many infected people exhibit low rates of increase in the numbers of infected people subsequently. This paper uses prefectural panel data from Japan through March 2021 to confirm the convergence process.

Epidemiology of massive hepatocellular carcinoma in dogs: A 4-year retrospective study

Hepatocellular carcinoma (HCC) is the most common primary liver tumour in dogs. However, the clinical features and risk factors of HCC have not been confirmed. The objective of this study was to investigate the clinical features and risk factors for canine HCC. Medical records of 44 dogs diagnosed with HCC at Hokkaido University Veterinary Teaching Hospital between 2013 and 2017 were retrospectively reviewed. All dogs evaluated at the teaching hospital during the study period were used as the reference population for breed, age, sex predispositions or possible related factors for HCC, including concurrent disorders. Clinical characteristics of HCC were determined using propensity score matching analysis. The prevalence of HCC diagnosis was 0.96%. Multivariate analysis revealed that dogs diagnosed with HCC were significantly older (odds ratio [OR], 1.20; 95% confidence intervals [CI], 1.07-1.33) than the reference population. Welsh Corgis (OR, 3.68; 95% CI, 1.56-8.67) and Beagles (OR, 4.33; 95% CI, 1.58-11.90) were significantly predisposed to HCC. Twenty-seven of 44 dogs with HCC had at least one concurrent disorder. The most common concurrent disorder was hyperadrenocorticism (n = 10), and the adjusted odds of hyperadrenocorticism in dogs with HCC were 4.13 higher than those of the reference population (95% CI, 1.95-8.76). Propensity score matching analysis revealed that thrombocytosis (n = 30/43), increased alanine aminotransferase (n = 41/44), increased alkaline phosphatase (n = 42/44), and hypercalcemia (n = 13/32) were significantly associated with HCC diagnosis. The results of this study suggest that Welsh Corgis and Beagles are breeds with a predisposition for HCC and that hyperadrenocorticism might be a potential risk factor.

Impact of surgical margins on survival of 37 dogs with massive hepatocellular carcinoma

AIMS

To compare the survival of dogs with completely resected massive hepatocellular carcinoma (HCC) with that of dogs in which HCC were incompletely excised.

METHODS

A retrospective cohort study was conducted. Dogs that underwent surgical excision of massive HCC between November 2006 and April 2015 were included. Dogs that died in the perioperative period or were lost to follow-up within 2 months after surgery were excluded. Data were collected from the medical records and a single pathologist examined all available histology slides to confirm the diagnosis of HCC. Surgical margins were defined as complete if no neoplastic cells were seen at the edge of excised tissues, based on original histopathology reports. Progression-free survival (PFS) and overall survival (OS) were compared between dogs with complete surgical margins (CM) and those with incomplete margins (IM) using a log-rank test.

RESULTS

Of the 37 dogs included in the study, 25 were allocated to the CM group and 12 to the IM group. Progressive local disease developed after surgery in three dogs in the CM group and seven dogs in the IM group. Three dogs in the CM group and five dogs in the IM group died due to tumour progression. Median PFS was longer for dogs in the CM group (1,000 (95% CI=562-1,438) days) compared to dogs in the IM group (521 (95% CI=243-799) days; p=0.007). OS was also longer for dogs in the CM group (>1,836 days) compared to those in the IM group (median 765 (95% CI=474-1,056) days; p=0.02).

CONCLUSIONS AND CLINICAL RELEVANCE

Compared with complete resection, incomplete resection decreased PFS and OS in dogs with massive HCC. Dogs with incompletely excised HCC should be closely monitored for local recurrence, although median OS was >2 years following incomplete excision. Further prospective studies are warranted to confirm these findings.

Abstract P5-11-03: Difference between 1st and 2nd generation serotonin receptor antagonists in triplet antiemetic therapy for highly emetogenic chemotherapy in breast cancer patients – according to recent multi-institutional double-blind randomized clinical research on the AC regimen

<Background>

The information presented herein extends our recent study of TTT (Trial for Triplet Antiemetic Therapy).

One of our main clinical questions has been whether a 2nd generation serotonin receptor antagonist (5-HT3ra) would be superior to 1st generation 5-HT3ra when administering triplet antiemetic therapy for the prevention of chemotherapy induced nausea & vomiting (CINV), since a prior Japanese trial demonstrated palonosetron to be superior to granisetron for controlling the delayed phase of CINV induced by highly emetogenic chemotherapy (HEC) and to doublet antiemetic therapy including dexamethasone for anthracycline and cyclophosphamide containing regimens (AC).

<Objectives>

In this study, we assessed the efficacies of 1st and 2nd generation 5-HT3ra agents for use as triplet antiemetic therapy for AC, by monitoring CINV, focusing especially daily CR in the delayed phase.

<Material and method>

Between 2012 and 2015, 491 women with breast cancer receiving AC were recruited from 11 institutions in Japan, and randomly assigned to either single-dose palonosetron (0.75mg) or granisetron (40μg/kg) prior to chemotherapy on day 1, both with dexamethasone (9.9 mg intravenously) and aprepitant (125mg orally) on day 1 followed by additional doses (80mg orally) on days 2 and 3. Age, institution and habitual alcohol intake were used as stratification factors. The primary endpoint was a complete response (CR). Statistical analysis was done by Mantel-Haenszel Method. This trial was registered with UMIN000007882.

<Results>

All 491 patients were included in efficacy analyses (ITT): 246 patients in the palonosetron group and 245 in the granisetron group. We previously reported that the difference in CR during the delayed phase, i.e. 24 hours after the administration of AC, did not reach statistical significance (53.8% vs 58.5%) in MASCC 2016. However, daily CR in the palonosetron group was much higher than that in the granisetron group after 48 hours.

<Conclusions>

Palonosetron showed better efficacy in controlling CINV during the late period of the delayed phase, i.e. 48 hours after AC administration, than granisetron as triplet antiemetic therapy for AC.

<Considerations>

The pattern of CINV reportedly shows two peaks including an acute phase caused by serotonin and a delayed phase caused by substance P, though the pattern of CINV with triplet antiemetic therapy administration might be different if the suppression of each of these peaks were to be achieved more efficiently. CINV may not be divided into two phases in the future, or the borderline area between the acute and delayed phases may require revision. The analysis of the late period of the delayed phase was ad hoc in this trial. However, when conducting studies related to CINV, it might be worthwhile to revise the borderline area between the two phases of CINV to facilitate elucidating the mechanisms underlying this potentially debilitating side effect of chemotherapy.

Citation Format: Ogata H, Saito M, Tsuneizumi M, Kutomi G, Hosoya K, Kawai Y, Sugizaki K, Katsumata N, Senuma K, Kitabatake T, Suda M, Uomori T, Miura K, Kurata M, Nitta Y, Yonemoto N, Matsuoka J. Difference between 1st and 2nd generation serotonin receptor antagonists in triplet antiemetic therapy for highly emetogenic chemotherapy in breast cancer patients – according to recent multi-institutional double-blind randomized clinical research on the AC regimen [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-11-03.

Placebo-controlled study with OHIO chamber of prophylactic pranlukast for children with Japanese cedar pollinosis: TOPIC-J III study

Objective

This double-blind, placebo-controlled comparative study was designed to investigate whether pranlukast dry syrup, a leukotriene receptor antagonist, has a protective effect against priming, controlled pollen exposure, and natural pollen exposure in children with Japanese cedar pollinosis.

Research design and methods

Thirty children aged 12–15 years with Japanese cedar pollinosis (positive skin test for Japanese cedar pollen), who had suffered from pollinosis for at least 2 years and developed severe nasal obstruction when exposed to Japanese cedar pollen, were enrolled in this study. They were randomly allocated to treatment with pranlukast or placebo orally after breakfast and dinner for 8 weeks during the Japanese cedar pollen season. Soon after the start of the pollen season, all subjects underwent a challenge by exposure for 3 h to Japanese cedar pollen (8000 grains/m³) in an artificial exposure chamber (OHIO chamber).

Clinical trial registration

The University Hospital Medical Information Network in Japan (UMIN000009840).

Main outcome measures

The effect of pranlukast was evaluated using self-rating of nasal symptoms by the subjects and measurement of eosinophil cationic protein in nasal discharge specimens.

Results

Scores for the symptoms of pollinosis were lower in the pranlukast group than in the placebo group during treatment in the priming state, as well as after controlled pollen exposure and natural pollen exposure. Pranlukast significantly improved the score for nasal obstruction, compared with placebo. A correlation was found between changes of the scores for symptoms of pollinosis and changes of the eosinophil cationic protein level.

Conclusions

These results confirm a protective effect of pranlukast against both priming and challenge (controlled and natural) with Japanese cedar pollen. The present findings suggested that pranlukast dry syrup may be useful for prophylaxis against pollinosis in children.

Comparative analysis of mRNA expression of surface antigens between histiocytic and nonhistiocytic sarcoma in dogs

Background

Definitive diagnosis of histiocytic sarcoma (HS) in dogs is relatively difficult by conventional histopathological examination because objective features of HS are not well defined.

Hypothesis

Quantitative analysis of mRNA expression of selected cellular surface antigens (SAs) specific to HS in dogs can facilitate objective and rapid diagnosis.

Animals

Dogs with HS (n = 30) and dogs without HS (n = 36), including those with other forms of lymphoma (n = 4), inflammatory diseases (n = 6), and other malignant neoplasias (n = 26).

Methods

Retrospective clinical observational study. Specimens were collected by excisional biopsy, needle core biopsy, or fine needle aspiration. To determine HS detection efficacy, mRNA expression levels of selected SAs specific to HS in dogs, including MHC class IIα, CD11b, CD11c, and CD86, were quantitatively analyzed using real‐time quantitative polymerase chain reaction.

Results

Each SA mRNA expression level was significantly higher in HS dogs than in non‐HS dogs (P = .0082). Cutoff values for discriminating between HS and non‐HS dogs based on these expression levels were calculated on the basis of receiver‐operating characteristic analysis. Accuracy of the cutoff values, including MHC class IIα, CD11b, CD11c, and CD86, was 87.9, 86.4, 86.4, and 84.8%, respectively.

Conclusions and Clinical Importance

Our results suggest that quantitative analysis of mRNA expression of the selected SAs could be an adjunctive diagnostic technique with high diagnostic accuracy for HS in dogs. Substantial investigation is required for exclusion of diseases with similar cell types of origin to lymphoma.

Transparent-Scaled Variant of the Rosy Bitterling, Rhodeus ocellatus ocellatus (Teleostei: Cyprinidae)

Transparent-scaled variant (TSV) of the rosy bitterling Rhodeus ocellatus ocellatus (Kner) was observed on both morphology and heredity. Compared with the normal-scaled type (NST), TSV is characterized by the blackish coloration in both eyes and peritoneum, and the luminescent one over the whole body. Histologically, the density of guanophores containing reflecting platelets was conspicuously low, especially in scale, iris, choroid and peritoneum, while the increase in the number of goblet cells (mucous cells) was recognized all over the dermal/epidermal regions. The heredity of TSV was recessive and supposed to be controlled by a single pair of genes unrelated to sex, judging from the result of crossbreeding experiments between NST and TSV. In growth and reproduction, no difference was seen between these two phenotypes. Transparent-scaled variant of the rosy bitterling can be competent for a genetic marker in experimental and developmental biology.

Role of mineralocorticoid receptor/Rho/Rho-kinase pathway in obesity-related renal injury

OBJECTIVE:

We examined whether aldosterone/Rho/Rho-kinase pathway contributed to obesity-associated nephropathy.

SUBJECTS:

C57BL/6J mice were fed a high fat or low fat diet, and mice on a high fat diet were treated with a mineralocorticoid receptor antagonist, eplerenone.

RESULTS:

The mice on a high fat diet not only developed obesity, but also manifested renal histological changes, including glomerular hypercellularity and increased mesangial matrix, which paralleled the increase in albuminuria. Furthermore, enhanced Rho-kinase activity was noted in kidneys from high fat diet-fed mice, as well as increased expressions of inflammatory chemokines. All of these changes were attenuated by eplerenone. In high fat diet-fed mice, mineralocorticoid receptor protein levels in the nuclear fraction and SGK1, an effector of aldosterone, were upregulated in kidneys, although serum aldosterone levels were unaltered. Furthermore, aldosterone and 3β-hydroxysteroid dehydrogenase in renal tissues were upregulated in high fat diet-fed mice. Finally, in cultured mesangial cells, stimulation with aldosterone enhanced Rho-kinase activity, and pre-incubation with eplerenone prevented the aldosterone-induced activation of Rho kinase.

CONCLUSION:

Excess fat intake causes obesity and renal injury in C57BL/6J mice, and these changes are mediated by an enhanced mineralocorticoid receptor/Rho/Rho-kinase pathway and inflammatory process. Mineralocorticoid receptor activation in the kidney tissue and the subsequent Rho-kinase stimulation are likely to participate in the development of obesity-associated nephropathy without elevation in serum aldosterone levels.

Gene silencing of STAT6 with siRNA ameliorates contact hypersensitivity and allergic rhinitis

BACKGROUND

Silencing of genes using small interfering RNA (siRNA) is a recently developed strategy to regulate the synthesis of target molecules. Signal transducer and activator of transcription 6 (STAT6) is a nuclear transcription factor that mediates Th2-type immunity.

METHODS

To elucidate the therapeutic potential of using siRNA to inhibit STAT6 in allergic reactions, we determined the nucleotide sequences of siRNA specific for STAT6.

RESULTS

The selected sequences of STAT6 siRNA specifically inhibited the generation of STAT6 synthesis in dermal fibroblasts and eotaxin (CCL11) production in response to IL-4/TNF-α in vitro. Local administration of STAT6 siRNA in vivo alleviated contact hypersensitivity responses to chemical haptens. This was accompanied by reduced local production of IL-4, IL-13, eotaxin (CCL11), TARC (CCL17) and MDC (CCL22). Similarly, consecutive intranasal instillation of STAT6 siRNA markedly inhibited inflammatory cellular infiltration of mucosal tissues in allergic rhinitis responses in association with reduced IL-4 and IL-5 production from regional lymph node cells. Immediate responses, such as sneezing and nasal rubbing behaviors, were also improved by STAT6 siRNA.

CONCLUSIONS

Local administration of STAT6 siRNA is thus a promising therapeutic strategy for both Th2-mediated cutaneous diseases and allergic rhinitis.

Plasma leptin concentration in dogs: effects of body condition score, age, gender and breeds

Leptin is a cytokine produced by adipocytes, and plays a key role in the regulation of energy balance. In the present study, we measured plasma leptin concentrations of 166 normal and obese dogs visiting veterinary practices, and clarified the influence of age, gender and breed on plasma leptin levels in dogs. Leptin levels were higher in the dogs with higher body condition scores. There was no noticeable influence of age, gender and breed, but those in optimal puppies and obese Miniature Dachshund tended to be lower than those in corresponding groups. We conclude that plasma leptin is a reliable marker of adiposity in dogs regardless of age, gender and breed variations, and thereby useful as a blood biochemistry test for health examinations and treatment of obesity.

Trends in demographics and survival for patients (pts) with advanced non-small cell lung cancer (NSCLC)

7114

Background: In clinical trials, concurrent chemoradiotherapy improves survival of pts with inoperable stage III NSCLC compared with sequential chemoradiotherapy or radiotherapy alone, and platinum doublets with third-generation chemotherapy prolong survival of pts with stage IV NSCLC. Epidermal growth factor receptor antagonist is active as second-line chemotherapy. Few outcomes research regarding demographics and survival trends in advanced NSCLC has been conducted. Methods: The National Cancer Center Hospital East Database was searched for all pts with inoperable stage III and IV NSCLC. Data was recorded for histology, age, sex, smoking history, tumor location, stage, performance status (PS), and treatment modality. Pts were divided into two groups; group A: newly registered pts from July 1992 to December 1997, group B: from January 1998 to June 2004. Survival curves were evaluated using the Kaplan-Meier methods, and statistical significance was estimated by the log-rank test. Results: 2,135 pts (771 pts group A vs. 1364 pts group B) were identified. Pts demographics of each group (% group A/B) were as follows; male; 74/77, non-smoker; 19/19, PS 0–1; 79/85, squamous cell histology; 26/24, stage III; 45/44. Median age was 63 years old in group A and 64 in group B. Median survival (MS), 1-year survival rate (1ys), 2ys and 3ys were 8 months (M), 33%, 12% and 7% in group A, 10M, 42%, 23% and 14% in group B, respectively (P < .0001). In pts with stage III, MS, 1ys, 2ys, 3ys were 12M, 46%, 20%, 12% in group A and 15M, 56%, 34%, 20% in group B (P < .0001). In non-smoker, MS, 1 ys, 2 ys were 11 M, 46%, 19% in group A and 15 M, 56%, 30% in group B (P < .0001). In females, MS, 1 ys, 2 ys were 10 M, 39%, 16% in group A and 15 M, 55%, 31% in group B (P < .0001). Conclusion: Although there were no apparent differences in demographics between the two groups, survival was significantly improved chronologically. The improvement was prominent in stage III, non-smokers and females suggesting the benefit of chemoradiotherapy and tyrosine kinase inhibitors.

[Table: see text]

Powdery mildew (Sphaerotheca fuliginea) resistance in melon is selectable at the haploid level

The major cause of powdery mildew in melons (Cucumis melo L.) is the fungus Sphaerotheca fuliginea. There are several cultivar- and season-specific races of this fungus. In order to control powdery mildew, it is important to introduce resistance to fungal infection into new cultivars during melon breeding. Haploid breeding is a powerful tool for the production of pure lines. In this study, it was investigated whether powdery mildew resistance could be manifested at the haploid level from two disease-resistant melon lines, PMR 45 and WMR 29. the effects of various races of S. fuliginea on diploid and haploid plants of PMR 45 and WMR 29 and of a disease-susceptible line, Fuyu 3 were measured. The responses of haploid and diploid plants to powdery mildew were identical. In addition, haploids that were generated from hybrids between Fuyu 3 and disease-resistant lines were examined. Seven out of 13 haploids from a Fuyu 3xPMR 45 cross and 10 out of 12 haploids from a Fuyu 3xWMR 29 cross were classified as resistant plants because they showed the same responses as their disease-resistant diploid parents to the various fungal races. These results indicate that resistance in PMR 45 and WMR 29 is selectable at the haploid level. All of the plant responses were observed by microscopy. A possible mechanism for generating powdery mildew resistance in two different melon lines is discussed.

MCT1-mediated transport of L-lactic acid at the inner blood-retinal barrier: a possible route for delivery of monocarboxylic acid drugs to the retina

PURPOSE

The aim of this study was to characterize L-lactic acid transport using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB2) as a model of in vitro inner blood-retinal barrier (iBRB) to obtain a better understanding of the transport mechanism at the iBRB.

METHODS

TR-iBRB2 cells were cultured at 33 degrees C, and L-lactic acid uptake was monitored by measuring [14C]L-lactic acid at 37 degrees C. The expression and mRNA level of monocarboxylate transporter (MCT)1 and MCT2 were determined by reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR with specific primers, respectively.

RESULTS

The [14C]L-lactic acid uptake by TR-iBRB2 cells increased up to a pH of 5.0 and was inhibited in the presence of 10 mM L-lactic acid. The [14C]L-lactic acid uptake at pH 6.0 was both temperature- and concentration-dependent with a Michaelis-Menten constant of 1.7 mM and a maximum uptake rate of 15 nmol/(30 s mg of protein). This process was reduced by carbonylcyanide p-trifluoromethoxyphenylhydrazone (protonophore), alpha-cyano-4-hydroxycinnamate, and p-chloromercuribenzenesulfonate (typical inhibitors for H+-coupled monocarboxylic acid transport), suggesting that L-lactic acid uptake by TR-iBRB2 cells is a carrier-mediated transport process coupled with an H+ gradient. [14C]L-Lactic acid uptake was markedly inhibited by monocarboxylic acids but not dicarboxylic acids and amino acids. Moreover, salicylic and valproic acids competitively inhibited this process with an inhibition constant of 4.7 mM and 5.4 mM, respectively. Although MCT1 and MCT2 mRNA were found to be expressed in TR-iBRB2 cells, MCT1 mRNA was found to be present at a concentration 33-fold greater than that of MCT2 mRNA using quantitative real-time PCR. [14C]L-Lactic acid was significantly reduced by 5-(N,N-hexamethylene)-amiloride at pH 7.4 and Na+/H+ exchanger I mRNA was expressed in TR-iBRB2 cells.

CONCLUSION

L-Lactic acid transport at the iBRB is an H-coupled and carrier-mediated mechanism via MCT1 that is competitively inhibited by monocarboxylate drugs.

Preparation strategy for uniformly sized, polymer-based HPLC packing materials having practically acceptable column efficiency. 1. Copolymerization technique

Uniformly sized, polymer-based packing materials affording excellent chromatographic performance in semimicro HPLC were prepared from mixtures of alkyl methacrylate and glycerol dimethacrylate by a copolymerization technique using a multistep swelling and polymerization method. A column efficiency of up to 13000 plates was obtained for a 2-mm-i.d. x 150-mm column with beads prepared from a 1:1 (v:v) mixture of an alkyl methacrylate and glycerol dimethacrylate. The packing materials exhibit a considerable improvement in column efficiency, as demonstrated on the separation of polyaromatic hydrocarbons (PAHs) having a relatively long retention time, which thus far has been a serious problem of polymer-based packing materials. Detailed studies suggested a rather limited optimum pore size, and its distribution was depicted to get the excellent column efficiency on polymer-based packing materials.

MCT1-mediated transport of L-lactic acid at the inner blood-retinal barrier: a possible route for delivery of monocarboxylic acid drugs to the retina

PURPOSE

The aim of this study was to characterize L-lactic acid transport using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB2) as a model of in vitro inner blood-retinal barrier (iBRB) to obtain a better understanding of the transport mechanism at the iBRB.

METHODS

TR-iBRB2 cells were cultured at 33 degrees C, and L-lactic acid uptake was monitored by measuring [14C]L-lactic acid at 37 degrees C. The expression and mRNA level of monocarboxylate transporter (MCT)1 and MCT2 were determined by reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time RT-PCR with specific primers, respectively.

RESULTS

The [14C]L-lactic acid uptake by TR-iBRB2 cells increased up to a pH of 5.0 and was inhibited in the presence of 10 mM L-lactic acid. The [14C]L-lactic acid uptake at pH 6.0 was both temperature- and concentration-dependent with a Michaelis-Menten constant of 1.7 mM and a maximum uptake rate of 15 nmol/(30 s mg of protein). This process was reduced by carbonylcyanide p-trifluoromethoxyphenylhydrazone (protonophore), alpha-cyano-4-hydroxycinnamate, and p-chloromercuribenzenesulfonate (typical inhibitors for H+-coupled monocarboxylic acid transport), suggesting that L-lactic acid uptake by TR-iBRB2 cells is a carrier-mediated transport process coupled with an H+ gradient. [14C]L-Lactic acid uptake was markedly inhibited by monocarboxylic acids but not dicarboxylic acids and amino acids. Moreover, salicylic and valproic acids competitively inhibited this process with an inhibition constant of 4.7 mM and 5.4 mM, respectively. Although MCT1 and MCT2 mRNA were found to be expressed in TR-iBRB2 cells, MCT1 mRNA was found to be present at a concentration 33-fold greater than that of MCT2 mRNA using quantitative real-time PCR. [14C]L-Lactic acid was significantly reduced by 5-(N,N-hexamethylene)-amiloride at pH 7.4 and Na+/H+ exchanger I mRNA was expressed in TR-iBRB2 cells.

CONCLUSION

L-Lactic acid transport at the iBRB is an H-coupled and carrier-mediated mechanism via MCT1 that is competitively inhibited by monocarboxylate drugs.

Chromosomal sublocalization and microsatellite DNA polymorphism of human adrenomedullin gene

Adrenomedullin (AM) is a hypotensive peptide widely produced in the cardiovascular organs and tissues such as the heart, kidney and vascular cells. We have cloned and sequenced genomic DNA encoding the human AM gene. In this study, we determined that the AM gene was located in the short arm of chromosome 11 (p15.1-3). The 3'-end of the gene is flanked by a microsatellite marker of cytosine adenine (CA) repeats. Moreover, we analyzed this DNA variation in the AM gene in the general Japanese population. Genomic DNA was obtained from the peripheral leukocytes of healthy normotensive subjects, 327 men and 149 women, aged 51 +/- 8 years (mean +/- SD). The genomic DNA was subject to PCR using a fluorescence-labeled primer, and the number of CA repeats were determined via polyacrylamide gel electrophoresis (PAGE). Plasma AM concentration was measured by RIA and compared with respect to the number of CA repeats adjacent to the AM gene. In Japanese, four types of alleles with different CA-repeat numbers; 11, 13, 14 and 19, appear to exist. The frequencies of these alleles were as follows: 11 repeats, 28.8%; 13 repeats, 33.1%; 14 repeats, 35.0% and 19 repeats, 3.1%. This DNA variation does not seem to affect the transcription of the AM gene, because plasma concentrations of AM were not significantly different between the genotypes.

Microsatellite DNA polymorphism of human adrenomedullin gene in normotensive subjects and patients with essential hypertension

Adrenomedullin (AM) is a hypotensive peptide widely produced in the cardiovascular organs and tissues. We have cloned and sequenced the genomic DNA encoding the human AM gene and have determined that the gene is located in the short arm of chromosome 11. The 3'-end of the gene is flanked by the microsatellite marker of cytosine adenine (CA) repeats. In this study, we investigated the association between DNA variations in AM gene and the predisposition to hypertension. Genomic DNA was obtained from 272 healthy normotensive subjects (NT) age 57+/-5 years and 266 patients with essential hypertension (EH) age 53+/-11 years. The DNA was subject to PCR using a fluorescence-labeled primer, and the number of CA repeats were determined by poly-acrylamide gel electrophoresis. The averaged blood pressure was 117+/-13/73+/-9 mm Hg in NT and 170+/-23/104+/-12 mm Hg in EH. In Japanese, there existed 4 types of alleles with different CA-repeat numbers: 11, 13, 14, and 19. The frequencies of these alleles were significantly different between NT and EH (chi(2)=9.43, P=0.024). Namely, 13.5% of EH carried the 19-repeat allele, whereas the frequency was 6.2% in NT (chi(2)=7.62, P=0.007). In NT, plasma AM concentrations were not significantly different between the genotypes. In conclusion, microsatellite DNA polymorphism of AM gene may be associated with the genetic predisposition to EH, although the gene expression is not likely to be affected by the genotypes.

Selectivity of stationary phases in reversed-phase liquid chromatography based on the dispersion interactions

Selectivity of 15 stationary phases was examined, either commercially available or synthesized in-house. The highest selectivity factors were observed for solute molecules having different polarizability on the 3-(pentabromobenzyloxy)propyl phase (PBB), followed by the 2-(1-pyrenyl)ethyl phase (PYE). Selectivity of fluoroalkane 4,4-di(trifluoromethyl)-5,5,6,6,7,7,7-heptafluoroheptyl (F13C9) phase is lowest among all phases for all compounds except for fluorinated ones. Aliphatic octyl (C8) and octadecyl (C18) phases demonstrated considerable selectivity, especially for alkyl compounds. While PBB showed much greater preference for compounds with high polarizability containing heavy atoms than C18 phase, F13C9 phase showed the exactly opposite tendency. These three stationary phases can offer widely different selectivity that can be utilized when one stationary phase fails to provide separation for certain mixtures. The retention and selectivity of solutes in reversed-phase liquid chromatography is related to the mobile phase and the stationary phase effects. The mobile phase effect, related to the hydrophobic cavity formation around non-polar solutes, is assumed to have a dominant effect on retention upon aliphatic stationary phases such as C8, C18. In a common mobile phase significant stationary phase effect can be attributed to dispersion interaction. Highly dispersive stationary phases such as PBB and PYE retain solutes to a significant extent by (attractive) dispersion interaction with the stationary phase ligands, especially for highly dispersive solutes containing aromatic functionality and/or heavy atoms. The contribution of dispersion interaction is shown to be much less on C18 or C8 phases and was even disadvantageous on F13C9 phase. Structural properties of stationary phases are analyzed and confirmed by means of quantitative structure-chromatographic retention (QSRR) study.

Conditionally immortalized retinal capillary endothelial cell lines (TR-iBRB) expressing differentiated endothelial cell functions derived from a transgenic rat

The objective of this study was to establish and characterize a retinal capillary endothelial cell line (TR-iBRB) from a newly developed transgenic rat harboring the temperature-sensitive simian virus 40 (SV 40) large T-antigen gene (Tg rat). Retinal capillary endothelial cells were isolated from a Tg rat and cultured in collagen-coated dishes at 37 degrees C for a period of 48 hr. Cells were subsequently cultured at 33 degrees C to activate the large T-antigen. At the third passage, cells were cloned by colony formation and isolated from other cells. Nine immortalized cell lines of retinal capillary endothelial cells (TR-iBRB1 approximately 9) were obtained from a Tg rat. These cell lines had a spindle-fiber shape morphology, expressed the typical endothelial marker, von Willebrand factor, and internalized acetylated-low density lipoprotein. Moreover, vascular endothelial growth factor (VEGF) receptor-2 was expressed in TR-iBRBs. TR-iBRBs expressed a large T-antigen and grew well at 33 degrees C with a doubling time of 19-21 hr. In contrast, cells did not grow at 37 and 39 degrees C due to the reduced expression of large T-antigen, supporting temperature-dependent cell growth. TR-iBRBs expressed GLUT1 and exhibited 3- O -methyl- D -glucose (3-OMG) uptake activity. This 3-OMG uptake was saturable with a Michaelis-Menten constant of 5.56 +/- 0.51 m M and a maximum uptake rate of 45.3 +/- 2.6 nmol min(-1) mg protein(-1). P-Glycoprotein, with a molecular weight of approximately 180 KDa, was expressed in TR-iBRBs. In addition, mdr 1a, mdr 1b and mdr 2 were detected in TR-iBRB2 using RT-PCR. In conclusion, conditionally immortalized retinal capillary endothelial cell lines were established from a transgenic rat harboring the temperature-sensitive SV 40 large T-antigen gene and these lines were shown to exhibit the properties of retinal capillary endothelial cells.

Conditionally immortalized cell lines as a new in vitro model for the study of barrier functions

Conditionally immortalized brain and retinal capillary endothelial and choroid plexus epithelial cell lines were established from a transgenic rat (Tg rat) and mouse (Tg mouse) harboring the temperature-sensitive simian virus 40 (ts SV 40) large T-antigen. These cell lines exhibit temperature-sensitive cell growth due to the expression of ts SV 40 large T-antigen. Mouse brain (TM-BBB) and rat brain (TR-BBB) and rat retinal (TR-iBRB) capillary endothelial cell lines appear to have a spindle-fiber shaped morphology and exhibit the typical endothelial markers, such as von Willebrand factor and acetylated low-density lipoprotein uptake. These cell lines express in vivo influx and efflux transporters, such as P-glycoprotein (P-gp) and GLUT1, which is capable of 3-O-methyl-D-glucose transport. TM-BBB cells are able to undergo efflux transport of cyclosporin A, which is a substrate for P-gp transport activity. They may also express oatp2 and exhibit dehydroepiandrosterone sulfate and digoxin uptake activity. TR-BBB cells express the mRNA of multidrug resistance associated protein 1 (MRP1) and a large neutral amino acid transporter, which consists of LAT1 and 4F2hc. TR-iBRB cells exhibit pH-dependent L-lactic acid transport activity and express the mRNA of monocarboxylate transporter (MCT) 1 and 2. The choroid plexus epithelial cell line (TR-CSFB) has polygonal cell morphology, expresses the typical choroid plexus epithelial cell marker, transthyretin, and has Na+, K+-ATPase located on the apical side. TR-CSFB cells also exhibit amino acid transport activity which has been observed in vivo. These barrier cell lines established from the Tg rat and Tg mouse have in vivo transport functions and are good in vitro models for drug transport to the brain and retina and as a screen for drugs which might be capable of delivery to the brain and retina.

Characterization of the amino acid transport of new immortalized choroid plexus epithelial cell lines: a novel in vitro system for investigating transport functions at the blood-cerebrospinal fluid barrier

PURPOSE

To establish and characterize a choroid plexus epithelial cell line (TR-CSFB) from a new type of transgenic rat harboring the temperature-sensitive simian virus 40 (ts SV 40) large T-antigen gene (Tg rat).

METHODS

Choroid plexus epithelial cells were isolated from the Tg rat and cultured on a collagen-coated dish at 37 degrees C during the first period of 3 days. Cells were subsequently cultured at 33 degrees C to activate large T-antigen. At the third passage, cells were cloned by colony formation and isolated from other cells using a penicillin cup.

RESULTS

Five immortalized cell lines of choroid plexus epithelial cells (TR-CSFB 1 approximately 5) were obtained from two Tg rats. These cell lines had a polygonal cell morphology, expressed the typical choroid plexus epithelial cell marker, transthyretin, and possessed Na+, K+-ATPase on their apical side. TR-CSFBs cells expressed a large T-antigen and grew well at 33 degrees C with a doubling-time of 35 approximately 40 hr. [3H]-L-Proline uptake by TR-CSFB cells took place in an Na+-dependent, ouabain-sensitive, energy-dependent, and concentration-dependent manner. It was also inhibited by alpha-methylaminoisobutylic acid, suggesting that system A for amino acids operates in TR-CSFB cells. When [3H]-L-proline uptake was measured using the Transwell device, the L-proline uptake rate following application to the apical side was five-fold greater than that following application to the basal side. In addition, both Na+-dependent and Na+-independent L-glutamic acid (L-Glu) uptake processes were present in TR-CSFB cells.

CONCLUSIONS

Immortalized choroid plexus epithelial cell lines were successfully established from Tg rats and have the properties of choroid plexus epithelial cells, and amino acid transport activity was observed in vivo.

Cloning and characterization of the gene encoding 3-hydroxy-3-methylglutaryl coenzyme A reductase in melon (Cucumis melo L. reticulatus)

We have isolated a cDNA for Cm-HMGR, encoding 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in melon (Cucumis melo L. reticulatus; Genbank Accession No. AB021862). Cm-HMGR encodes a polypeptide of 588 amino acids that contains two transmembrane domains and a catalytic domain. Database searches revealed that Cm-HMGR shows homology to HMG1 (63.7%) and HMG2 (70.3%) of tomato, to HMG1 (77.2%) and HMG2 (69.4%) of Arabidopsis thaliana, and to HMGR of tobacco (72.6%). Functional expression in a HMG-CoA reductase-deficient mutant yeast showed that Cm-HMGR products mediate the synthesis of mevalonate. Northern analysis revealed that the level of Cm-HMGR mRNA in the fruit increased after pollination and markedly decreased at the end of fruit enlargement. During ripening, Cm-HMGR mRNA levels increased markedly in the fruit. In parallel with mRNA expression, Cm-HMGR activity increased after pollination, whereas no Cm-HMGR activity was detectable during fruit ripening. Our results suggest that Cm-HMGR is important during early post-pollination development of the fruit in melon.

Blood-brain barrier is involved in the efflux transport of a neuroactive steroid, dehydroepiandrosterone sulfate, via organic anion transporting polypeptide 2

We have investigated the transport characteristics of dehydroepiandrosterone sulfate (DHEAS), a neuroactive steroid, at the blood-brain barrier (BBB) in a series of functional in vivo and in vitro studies. The apparent BBB efflux rate constant of [(3)H]DHEAS evaluated by the brain efflux index method was 2.68 x 10(-2) min(-1). DHEAS efflux transport was a saturable process with a Michaelis constant (K:(m)) of 32.6 microM: Significant amounts of [(3)H]DHEAS were determined in the jugular venous plasma by HPLC, providing direct evidence that most of the DHEAS is transported in intact form from brain to the circulating blood across the BBB. This efflux transport of [(3)H]DHEAS was significantly inhibited by common rat organic anion-transporting polypeptide (oatp) substrates such as taurocholate, cholate, sulfobromophthalein, and estrone-3-sulfate. Moreover, the apparent efflux clearance of [(3)H]DHEAS across the BBB (118 microl/min-g of brain) was 10.4-fold greater than its influx clearance estimated by the in situ brain perfusion technique (11.4 microl/min-g of brain), suggesting that DHEAS is predominantly transported from the brain to blood across the BBB. In cellular uptake studies using a conditionally immortalized mouse brain capillary endothelial cell line (TM-BBB4), [(3)H]DHEAS uptake by TM-BBB4 cells exhibited a concentration dependence with a K:(m) of 34.4 microM: and was significantly inhibited by the oatp2-specific substrate digoxin. Conversely, [(3)H]digoxin uptake by TM-BBB4 cells was significantly inhibited by DHEAS. Moreover, the net uptake of [(3)H]DHEAS at 30 min was significantly increased under ATP-depleted conditions, suggesting that an energy-dependent efflux process may also be involved in TM-BBB4. RT-PCR and sequence analysis suggest that an oatp2 is expressed in TM-BBB4 cells. In conclusion, DHEAS efflux transport takes place across the BBB, and studies involving in vitro DHEAS uptake and RT-PCR suggest that there is oatp2-mediated DHEAS transport at the BBB.

Masculinization mechanism of hybrids in bitterlings (Teleostei: Cyprinidae)

The sex ratio of bitterling hybrids (subfamily: Acheilognathinae) is often likely to be biased toward males. Artificial hybridization was carried out in 10 species of bitterlings (three genera) in order to elucidate the masculinization mechanism of hybrids. Tanakia himantegus never produced viable F1 hybrids with other species, while hybrids of most other species were viable. In terms of sex ratio and fertility, hybrids were clearly divided into two groups: congeneric Tanakia hybrids and others. Both male and female congeneric Tanakia hybrids were fertile. The sex ratio was nearly 1:1 in all groups of Tanakia hybrids. Except for the congeneric Tanakia hybrids, sterile males appeared predominantly in groups of hybrids in which females were very rare but remained fertile. Sterile intersexes were also observed in five hybrid groups: T. lanceolata (female) x Acheilognathus cyanostigma (male), Rhodeus uyekii (female) x T. lanceolata (male), A. rhombeus (female) x T. lanceolata (male), A. rhombeus (female) x T. limbata (male), and A. tabira tabira (female) x A. cyanostigma (male). In the development of male-predominant hybrids, although hybrid and control (parental species) hatching and survival rates do not differ, no females appeared in hybrids, contrary to the controls. Taking the female heterogametic sex-determining system (ZW) and the phylogenetic relationship of bitterlings into consideration, the masculinization mechanism of hybrids in bitterlings can be explained by the interaction of two sex chromosomes, derived from each parental species. The basic genetic sex in bitterlings is male (ZZ) and the derivative is female (ZW). When parental species are related, the sex phenotype of hybrids coincides with the genetic sex. However, when the parental species differ, the sex phenotype of the ZW genotype is reversed to become male by an abnormal interaction between the Z and W chromosomes. The rare appearance of females and intersexes in male-predominant hybrids might be due to complete or partial functional expression of the W chromosome.

Brain-to-blood efflux transport of estrone-3-sulfate at the blood-brain barrier in rats

Efflux transport of estrogens such as estrone-3-sulfate (E1S), and estrone (E1) across the blood-brain barrier (BBB) was evaluated using the Brain Efflux Index (BEI) method. The apparent BBB efflux rate constant (Keff) of [3H]E1S, and [3H]E1 was 6.63 x 10(-2) +/- 0.77 x 10(-2) min(-1), and 6.91 x 10(-2) +/- 1.23 x 10(-2) min(-1), respectively. The efflux transport of [3H]E1S from brain across the BBB was a saturable process with Michaelis constant (Km) of 96.0 +/- 34.4 microM and 93.4 +/- 22.0 microM estimated by two different methods. By determining [3H]E1S metabolites using high performance liquid chromatography (HPLC) after intracerebral injection, significant amounts of [3H]E1S were found in the jugular venous plasma, providing direct evidence that most of [3H]E1S is transported from brain across the BBB in intact form. To compare the apparent efflux clearance across the BBB of E1S with that of E1, the brain distribution volume of E1S and E1 was estimated using the brain slice uptake method. The apparent efflux clearance of [3H]E1S was determined to be 74.9 +/- 3.8 microl/(min x g brain) due to the distribution volume of 1.13 +/- 0.06 ml/g brain. By contrast, the apparent efflux clearance of E1 was more than 227 +/- 3 microl/(min x g brain), since the distribution volume of [3H]E1 at 60 min was 3.28 +/- 0.13 ml/g. The E1S efflux transport process was inhibited by more than 40% by coadministration of bile acids (taurocholate, and cholate), and organic anions (sulfobromophthalein, and probenecid), whereas other organic anions did not affect the E1S efflux transport. The [3H]E1S efflux was significantly reduced by 48.6% after preadministration of 5 mM dehydroepiandrosterone sulfate. These results suggest that E1S is transported from brain to the circulating blood across the BBB via a carrier-mediated efflux transport system.